Captive recoil springs, when used with semiautomatic pistols, are known to provide a significant advantage during assembly and disassembly of the pistol. Captive recoil springs according to the prior art are usually coil springs which surround a guide rod and are “captured” using a round end cap attached to the free end of the guide rod (i.e., the end which does not engage the frame or the barrel). The end cap must be dimensioned so that it is smaller than the outer diameter of the coil spring. This leaves an outer portion of the end of the coil spring exposed to permit engagement with the slide.
When coil springs are made from wire having a round cross section there is a very small difference between their inner and outer diameters, the difference being merely twice the diameter of the wire comprising the spring. Because this difference is small, the end cap which captures the spring and the diameter of the opening in the slide where the slide engages the end of the recoil spring must be made to tight tolerances commensurate with the small diameter of the wire and the diameter of the spring coils. There is clearly an opportunity to gain advantage by using a round wire coil spring with components which do not need to be made to the exacting tolerances associated with prior art captive recoil springs.